Northern China, in the plains around the Huang Ho (or Yellow River), bears evidence of more continuous human development than any other region on earth.

500,000 years ago Peking man lives in the caves at Zhoukoudian, about 30 miles (48km) southwest of the modern city of Beijing. This is the farthest north that Homo erectus has been found, and hearths in the caves are probably the earliest evidence of the human use of fire. The same caves are occupied 20,000 years ago by modern man, Homo sapiens sapiens, during the Stone Age. And 3500 years ago a nearby river valley becomes the site of one of the first great civilizations.

The Shang dynasty: 1600 - 1100 BC

The city of An-yang, rediscovered in the 20th century, is an important centre of the first Chinese civilization - that of the Shang dynasty, which lasts from about 1600 to 1100 BC. Known to its occupants as the Great City Shang, its buildings are on both banks of the Huan river, to the north of the Yellow River.

An-yang is at the heart of a society in which human sacrifice plays a significant role. Archaeology reveals this, as does an extraordinary archive of written records - stored on what the peasants of this area, in modern times, have believed to be dragon bones.

The dragon bones are the records, kept by the priests, of the questions asked of the oracle by the Shang rulers. The answer is found by the method of divination known as scapulimancy.

The priest takes a polished strip of bone, usually from the shoulder blade of an ox, and cuts in it a groove to which he applies a heated bronze point. The answer to the question (in most cases just yes or no) is revealed by the pattern of the cracks which appear in the bone. With the bureaucratic thoroughness of civil servants, the priests then write on the bone the question that was asked, and sometimes the answer that was given, before filing the bone away in an archive (see Questions and answers on oracle bones).

Sacrifice, silk and bronze: 1600 - 1100 BC

Several of the inscriptions on the oracle bones mention sacrifices, sometimes of prisoners of war, which are to be made to a silkworm goddess. There is even a Shang court official called Nu Cang, meaning Mistress of the Silkworms.

Silk, China's first great contribution to civilization, has been an important product of the region for at least 1000 years before the Shang dynasty and the beginning of recorded history. The earliest silk fragments unearthed by archaeologists date from around 2850 BC.

The writing on the Shang oracle bones is in pictorial characters which evolve, often with only minor modifications, into the characters used in written Chinese today - 3500 years later. There can be no better example of the continuity underpinning Chinese civilization.

The excavations at An-yang demonstrate that Shang craftsmen have reached an astonishing level of skill in the casting of bronze. And they reveal a reckless attitude to human life. A building cannot be consecrated at An-yang, or a ruler buried, without extensive human sacrifice (see the Sacrificial guardians of An-yang).

The roots of Chinese culture: 1600 - 1100 BC

The area controlled by the Shang rulers is relatively small, but Shang cultural influence spreads through a large part of central China. In addition to their writing of Chinese characters, the Shang introduce many elements which have remained characteristic of this most ancient surviving culture. Bronze chopsticks, for example, have been found in a Shang tomb.

The Shang use a supremely confident name for their own small territory; it too has stood the test of time. They call An-yang and the surrounding region Chung-kuo, meaning 'the Central Country'. It is still the Chinese name for China. And the Shang practise another lasting Chinese tradition - the worship of ancestors.

Most of the elaborate bronze vessels made in Shang times are for use in temples or shrines to ancestors. The richly decorated urns are for cooking the meat of the sacrificed animals. The most characteristic design is the li, with its curved base extended into three hollow protuberances - enabling maximum heat to reach the sacrificial stew.

The bronze jugs, often fantastically shaped into weird animals and birds, are for pouring a liquid offering to the ancestor - usually a hot alcoholic concoction brewed from millet.

In Shang society ancestor worship is limited to the king and a few noble families. The good will of the king's ancestors is crucial to the whole of society, because they are the community's link with the gods. Over the centuries the king becomes known as the Son of Heaven. The shrine to his ancestors - the Temple of Heaven in Beijing - is the focal point of the national religion.

In subsequent dynasties, and particularly after the time of Confucius, ancestor worship spreads downwards through the Chinese community. It becomes a crucial part of the culture of the Confucian civil servants, the mandarins.